Documentation for GHANDLE.
[simpleserver-moved-to-github.git] / SimpleServer.xs
index 4c047e5..2062ac3 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * $Id: SimpleServer.xs,v 1.40 2006-04-10 20:49:24 adam Exp $ 
+ * $Id: SimpleServer.xs,v 1.63 2007-05-23 10:22:00 sondberg Exp $ 
  * ----------------------------------------------------------------------
  * 
  * Copyright (c) 2000-2004, Index Data.
 #include <yaz/backend.h>
 #include <yaz/log.h>
 #include <yaz/wrbuf.h>
+#include <yaz/querytowrbuf.h>
 #include <stdio.h>
+#include <yaz/mutex.h>
+#include <yaz/oid_db.h>
 #ifdef WIN32
 #else
 #include <unistd.h>
@@ -50,7 +53,7 @@
 #define sv_undef PL_sv_undef
 #endif
 
-NMEM_MUTEX simpleserver_mutex;
+YAZ_MUTEX simpleserver_mutex;
 
 typedef struct {
        SV *handle;
@@ -64,6 +67,7 @@ typedef struct {
        SV *esrequest_ref;
        SV *delete_ref;
        SV *scan_ref;
+       SV *explain_ref;
        NMEM nmem;
        int stop_flag;  /* is used to stop server prematurely .. */
 } Zfront_handle;
@@ -79,10 +83,10 @@ SV *present_ref = NULL;
 SV *esrequest_ref = NULL;
 SV *delete_ref = NULL;
 SV *scan_ref = NULL;
+SV *explain_ref = NULL;
 PerlInterpreter *root_perl_context;
-int MAX_OID = 15;
 
-#define GRS_BUF_SIZE 512
+#define GRS_BUF_SIZE 8192
 
 CV * simpleserver_sv2cv(SV *handler) {
     STRLEN len;
@@ -126,7 +130,7 @@ void tst_clones(void)
 
 int simpleserver_clone(void) {
 #ifdef USE_ITHREADS
-     nmem_mutex_enter(simpleserver_mutex);
+     yaz_mutex_enter(simpleserver_mutex);
      if (1)
      {
          PerlInterpreter *current = PERL_GET_CONTEXT;
@@ -142,14 +146,14 @@ int simpleserver_clone(void) {
              PERL_SET_CONTEXT( perl_interp );
          }
      }
-     nmem_mutex_leave(simpleserver_mutex);
+     yaz_mutex_leave(simpleserver_mutex);
 #endif
      return 0;
 }
 
 
 void simpleserver_free(void) {
-    nmem_mutex_enter(simpleserver_mutex);
+    yaz_mutex_enter(simpleserver_mutex);
     if (1)
     {
         PerlInterpreter *current_interp = PERL_GET_CONTEXT;
@@ -164,7 +168,7 @@ void simpleserver_free(void) {
             perl_free(current_interp);
        }
     }
-    nmem_mutex_leave(simpleserver_mutex);
+    yaz_mutex_leave(simpleserver_mutex);
 }
 
 
@@ -192,7 +196,7 @@ Z_GenericRecord *read_grs1(char *str, ODR o)
                }
                len = ptr - str;
                if (len > GRS_BUF_SIZE) {
-                   yaz_log(LOG_WARN, "GRS string too long - truncating (%d > %d)", len, GRS_BUF_SIZE);
+                   yaz_log(YLOG_WARN, "GRS string too long - truncating (%d > %d)", len, GRS_BUF_SIZE);
                    len = GRS_BUF_SIZE;
                }
                strncpy(line, str, len);
@@ -207,7 +211,7 @@ Z_GenericRecord *read_grs1(char *str, ODR o)
                }
                if (sscanf(buf, "(%d,%[^)])", &type, value) != 2)
                {
-                       yaz_log(LOG_WARN, "Bad data in '%s'", buf);
+                       yaz_log(YLOG_WARN, "Bad data in '%s'", buf);
                        return r;
                }
                if (!type && *value == '0')
@@ -219,25 +223,22 @@ Z_GenericRecord *read_grs1(char *str, ODR o)
                        buf++;
                if (r->num_elements >= GRS_MAX_FIELDS)
                {
-                       yaz_log(LOG_WARN, "Max number of GRS-1 elements exceeded [GRS_MAX_FIELDS=%d]", GRS_MAX_FIELDS);
+                       yaz_log(YLOG_WARN, "Max number of GRS-1 elements exceeded [GRS_MAX_FIELDS=%d]", GRS_MAX_FIELDS);
                        exit(0);
                }
                r->elements[r->num_elements] = t = (Z_TaggedElement *) odr_malloc(o, sizeof(Z_TaggedElement));
-               t->tagType = (int *)odr_malloc(o, sizeof(int));
-               *t->tagType = type;
+               t->tagType = odr_intdup(o, type);
                t->tagValue = (Z_StringOrNumeric *)
                        odr_malloc(o, sizeof(Z_StringOrNumeric));
                if ((ivalue = atoi(value)))
                {
                        t->tagValue->which = Z_StringOrNumeric_numeric;
-                       t->tagValue->u.numeric = (int *)odr_malloc(o, sizeof(int));
-                       *t->tagValue->u.numeric = ivalue;
+                       t->tagValue->u.numeric = odr_intdup(o, ivalue);
                }
                else
                {
                        t->tagValue->which = Z_StringOrNumeric_string;
-                       t->tagValue->u.string = (char *)odr_malloc(o, strlen(value)+1);
-                       strcpy(t->tagValue->u.string, value);
+                       t->tagValue->u.string = odr_strdup(o, value);
                }
                t->tagOccurrence = 0;
                t->metaData = 0;
@@ -259,7 +260,6 @@ Z_GenericRecord *read_grs1(char *str, ODR o)
 
 
 
-
 static void oid2str(Odr_oid *o, WRBUF buf)
 {
     for (; *o >= 0; o++) {
@@ -271,70 +271,13 @@ static void oid2str(Odr_oid *o, WRBUF buf)
     }
 }
 
-
-static int rpn2pquery(Z_RPNStructure *s, WRBUF buf)
+WRBUF oid2dotted(Odr_oid *oid)
 {
-    switch (s->which) {
-       case Z_RPNStructure_simple: {
-           Z_Operand *o = s->u.simple;
-
-           switch (o->which) {
-               case Z_Operand_APT: {
-                   Z_AttributesPlusTerm *at = o->u.attributesPlusTerm;
-
-                   if (at->attributes) {
-                       int i;
-                       char ibuf[16];
-
-                       for (i = 0; i < at->attributes->num_attributes; i++) {
-                           wrbuf_puts(buf, "@attr ");
-                           if (at->attributes->attributes[i]->attributeSet) {
-                               oid2str(at->attributes->attributes[i]->attributeSet, buf);
-                               wrbuf_putc(buf, ' ');
-                           }
-                           sprintf(ibuf, "%d=", *at->attributes->attributes[i]->attributeType);
-                           assert(at->attributes->attributes[i]->which == Z_AttributeValue_numeric);
-                           wrbuf_puts(buf, ibuf);
-                           sprintf(ibuf, "%d ", *at->attributes->attributes[i]->value.numeric);
-                           wrbuf_puts(buf, ibuf);
-                       }
-                   }
-                   switch (at->term->which) {
-                       case Z_Term_general: {
-                           wrbuf_putc(buf, '"');
-                           wrbuf_write(buf, (char*) at->term->u.general->buf, at->term->u.general->len);
-                           wrbuf_puts(buf, "\" ");
-                           break;
-                       }
-                       default: abort();
-                   }
-                   break;
-               }
-               default: abort();
-           }
-           break;
-       }
-       case Z_RPNStructure_complex: {
-           Z_Complex *c = s->u.complex;
-
-           switch (c->roperator->which) {
-               case Z_Operator_and: wrbuf_puts(buf, "@and "); break;
-               case Z_Operator_or: wrbuf_puts(buf, "@or "); break;
-               case Z_Operator_and_not: wrbuf_puts(buf, "@not "); break;
-               case Z_Operator_prox: abort();
-               default: abort();
-           }
-           if (!rpn2pquery(c->s1, buf))
-               return 0;
-           if (!rpn2pquery(c->s2, buf))
-               return 0;
-           break;
-       }
-       default: abort();
-    }
-    return 1;
+    WRBUF buf = wrbuf_alloc();
+    oid2str(oid, buf);
+    return buf;
 }
-
+               
 
 WRBUF zquery2pquery(Z_Query *q)
 {
@@ -342,13 +285,8 @@ WRBUF zquery2pquery(Z_Query *q)
 
     if (q->which != Z_Query_type_1 && q->which != Z_Query_type_101) 
        return 0;
-    if (q->u.type_1->attributeSetId) {
-       /* Output attribute set ID */
-       wrbuf_puts(buf, "@attrset ");
-       oid2str(q->u.type_1->attributeSetId, buf);
-       wrbuf_putc(buf, ' ');
-    }
-    return rpn2pquery(q->u.type_1->RPNStructure, buf) ? buf : 0;
+    yaz_rpnquery_to_wrbuf(buf, q->u.type_1);
+    return buf;
 }
 
 
@@ -514,6 +452,103 @@ static SV *rpn2perl(Z_RPNStructure *s)
 }
 
 
+/* Decode the Z_SortAttributes struct and store the whole thing into the
+ * hash by reference
+ */
+int simpleserver_ExpandSortAttributes (HV *sort_spec, Z_SortAttributes *sattr)
+{
+    WRBUF attrset_wr = wrbuf_alloc();
+    AV *list = newAV();
+    Z_AttributeList *attr_list = sattr->list;
+    int i;
+
+    oid2str(sattr->id, attrset_wr);
+    hv_store(sort_spec, "ATTRSET", 7,
+             newSVpv(attrset_wr->buf, attrset_wr->pos), 0);
+    wrbuf_destroy(attrset_wr);
+
+    hv_store(sort_spec, "SORT_ATTR", 9, newRV( sv_2mortal( (SV*) list ) ), 0);
+
+    for (i = 0; i < attr_list->num_attributes; i++) 
+    {
+        Z_AttributeElement *attr = *attr_list->attributes++; 
+        HV *attr_spec = newHV();
+                
+        av_push(list, newRV( sv_2mortal( (SV*) attr_spec ) ));
+        hv_store(attr_spec, "ATTR_TYPE", 9, newSViv(*attr->attributeType), 0);
+
+        if (attr->which == Z_AttributeValue_numeric)
+        {
+            hv_store(attr_spec, "ATTR_VALUE", 10,
+                     newSViv(*attr->value.numeric), 0);
+        } else {
+            return 0;
+        }
+    }
+
+    return 1;
+}
+
+
+/* Decode the Z_SortKeySpec struct and store the whole thing in a perl hash */
+int simpleserver_SortKeySpecToHash (HV *sort_spec, Z_SortKeySpec *spec)
+{
+    Z_SortElement *element = spec->sortElement;
+
+    hv_store(sort_spec, "RELATION", 8, newSViv(*spec->sortRelation), 0);
+    hv_store(sort_spec, "CASE", 4, newSViv(*spec->caseSensitivity), 0);
+    hv_store(sort_spec, "MISSING", 7, newSViv(spec->which), 0);
+
+    if (element->which == Z_SortElement_generic)
+    {
+        Z_SortKey *key = element->u.generic;
+
+        if (key->which == Z_SortKey_sortField)
+        {
+            hv_store(sort_spec, "SORTFIELD", 9,
+                     newSVpv((char *) key->u.sortField, 0), 0);
+        }
+        else if (key->which == Z_SortKey_elementSpec)
+        {
+            Z_Specification *zspec = key->u.elementSpec;
+            
+            hv_store(sort_spec, "ELEMENTSPEC_TYPE", 16,
+                     newSViv(zspec->which), 0);
+
+            if (zspec->which == Z_Schema_oid)
+            {
+                WRBUF elementSpec = wrbuf_alloc();
+
+                oid2str(zspec->schema.oid, elementSpec);
+                hv_store(sort_spec, "ELEMENTSPEC_VALUE", 17,
+                         newSVpv(elementSpec->buf, elementSpec->pos), 0);
+                wrbuf_destroy(elementSpec);
+            }
+            else if (zspec->which == Z_Schema_uri)
+            {
+                hv_store(sort_spec, "ELEMENTSPEC_VALUE", 17,
+                         newSVpv((char *) zspec->schema.uri, 0), 0);
+            }
+        }
+        else if (key->which == Z_SortKey_sortAttributes)
+        {
+            return simpleserver_ExpandSortAttributes(sort_spec,
+                                                     key->u.sortAttributes);
+        }
+        else
+        {
+            return 0;
+        }
+    }
+    else
+    {
+        return 0;
+    }
+
+    return 1;
+}
+
+
 static SV *zquery2perl(Z_Query *q)
 {
     SV *sv;
@@ -534,15 +569,18 @@ int bend_sort(void *handle, bend_sort_rr *rr)
 {
        HV *href;
        AV *aref;
+        AV *sort_seq;
        SV **temp;
        SV *err_code;
        SV *err_str;
        SV *status;
+        SV *point;
        STRLEN len;
        char *ptr;
        char *ODR_err_str;
        char **input_setnames;
        Zfront_handle *zhandle = (Zfront_handle *)handle;
+        Z_SortKeySpecList *sort_spec = rr->sort_sequence;
        int i;
        
        dSP;
@@ -553,13 +591,32 @@ int bend_sort(void *handle, bend_sort_rr *rr)
        input_setnames = rr->input_setnames;
        for (i = 0; i < rr->num_input_setnames; i++)
        {
-               av_push(aref, newSVpv(*input_setnames++, 0));
+            av_push(aref, newSVpv(*input_setnames++, 0));
        }
+
+        sort_seq = newAV();
+        for (i = 0; i < sort_spec->num_specs; i++)
+        {
+            Z_SortKeySpec *spec = *sort_spec->specs++;
+            HV *sort_spec = newHV();
+
+            if ( simpleserver_SortKeySpecToHash(sort_spec, spec) )
+                av_push(sort_seq, newRV( sv_2mortal( (SV*) sort_spec ) ));
+            else
+            {
+                rr->errcode = 207;
+                return 0;
+            }
+        }
+        
        href = newHV();
        hv_store(href, "INPUT", 5, newRV( (SV*) aref), 0);
        hv_store(href, "OUTPUT", 6, newSVpv(rr->output_setname, 0), 0);
+        hv_store(href, "SEQUENCE", 8, newRV( (SV*) sort_seq), 0);
        hv_store(href, "HANDLE", 6, zhandle->handle, 0);
        hv_store(href, "STATUS", 6, newSViv(0), 0);
+        hv_store(href, "ERR_CODE", 8, newSViv(0), 0);
+        hv_store(href, "ERR_STR", 7, newSVpv("", 0), 0);
 
        PUSHMARK(sp);
 
@@ -580,23 +637,34 @@ int bend_sort(void *handle, bend_sort_rr *rr)
        temp = hv_fetch(href, "STATUS", 6, 1);
        status = newSVsv(*temp);
 
-       PUTBACK;
-       FREETMPS;
-       LEAVE;
+        temp = hv_fetch(href, "HANDLE", 6, 1);
+        point = newSVsv(*temp);
 
-       hv_undef(href),
+       hv_undef(href);
        av_undef(aref);
+        av_undef(sort_seq);
+       
+       sv_free( (SV*) aref);
+       sv_free( (SV*) href);
+       sv_free( (SV*) sort_seq);
+
        rr->errcode = SvIV(err_code);
        rr->sort_status = SvIV(status);
+        
        ptr = SvPV(err_str, len);
        ODR_err_str = (char *)odr_malloc(rr->stream, len + 1);
        strcpy(ODR_err_str, ptr);
        rr->errstring = ODR_err_str;
+        zhandle->handle = point;
 
        sv_free(err_code);
        sv_free(err_str);
        sv_free(status);
        
+        PUTBACK;
+       FREETMPS;
+       LEAVE;
+
        return 0;
 }
 
@@ -635,6 +703,8 @@ int bend_search(void *handle, bend_search_rr *rr)
 #endif
        href = newHV();         
        hv_store(href, "SETNAME", 7, newSVpv(rr->setname, 0), 0);
+       if (rr->srw_sortKeys && *rr->srw_sortKeys) 
+           hv_store(href, "SRW_SORTKEYS", 12, newSVpv(rr->srw_sortKeys, 0), 0);
        hv_store(href, "REPL_SET", 8, newSViv(rr->replace_set), 0);
        hv_store(href, "ERR_CODE", 8, newSViv(0), 0);
        hv_store(href, "ERR_STR", 7, newSVpv("", 0), 0);
@@ -693,7 +763,7 @@ int bend_search(void *handle, bend_search_rr *rr)
        sv_free( (SV*) aref);
        sv_free( (SV*) href);
        if (query)
-           wrbuf_free(query, 1);
+           wrbuf_destroy(query);
        PUTBACK;
        FREETMPS;
        LEAVE;
@@ -701,71 +771,6 @@ int bend_search(void *handle, bend_search_rr *rr)
 }
 
 
-/* ### this is worryingly similar to oid2str() */
-WRBUF oid2dotted(int *oid)
-{
-
-       WRBUF buf = wrbuf_alloc();
-       int dot = 0;
-
-       for (; *oid != -1 ; oid++)
-       {
-               char ibuf[16];
-               if (dot)
-               {
-                       wrbuf_putc(buf, '.');
-               }
-               else
-               {
-                       dot = 1;
-               }
-               sprintf(ibuf, "%d", *oid);
-               wrbuf_puts(buf, ibuf);
-       }
-       return buf;
-}
-               
-
-int dotted2oid(char *dotted, int *buffer)
-{
-        int *oid;
-        char ibuf[16];
-        char *ptr;
-        int n = 0;
-
-        ptr = ibuf;
-        oid = buffer;
-        while (*dotted)
-        {
-                if (*dotted == '.')
-                {
-                        n++;
-                       if (n == MAX_OID)  /* Terminate if more than MAX_OID entries */
-                       {
-                               *oid = -1;
-                               return -1;
-                       }
-                        *ptr = 0;
-                        sscanf(ibuf, "%d", oid++);
-                        ptr = ibuf;
-                        dotted++;
-
-                }
-                else
-                {
-                        *ptr++ = *dotted++;
-                }
-        }
-        if (n < MAX_OID)
-       {
-               *ptr = 0;
-               sscanf(ibuf, "%d", oid++);
-       }
-        *oid = -1;
-       return 0;
-}
-
-
 int bend_fetch(void *handle, bend_fetch_rr *rr)
 {
        HV *href;
@@ -778,18 +783,18 @@ int bend_fetch(void *handle, bend_fetch_rr *rr)
        SV *sur_flag;
        SV *point;
        SV *rep_form;
+       SV *schema = 0;
        char *ptr;
        char *ODR_record;
        char *ODR_basename;
        char *ODR_errstr;
-       int *ODR_oid_buf;
-       oident *oid;
        WRBUF oid_dotted;
        Zfront_handle *zhandle = (Zfront_handle *)handle;
        CV* handler_cv = 0;
 
        Z_RecordComposition *composition;
        Z_ElementSetNames *simple;
+       Z_CompSpec *complex;
        STRLEN length;
 
        dSP;
@@ -799,9 +804,14 @@ int bend_fetch(void *handle, bend_fetch_rr *rr)
        rr->errcode = 0;
        href = newHV();
        hv_store(href, "SETNAME", 7, newSVpv(rr->setname, 0), 0);
+       if (rr->schema)
+               hv_store(href, "SCHEMA", 6, newSVpv(rr->schema, 0), 0);
+        else
+                hv_store(href, "SCHEMA", 6, newSVpv("", 0), 0);
+
        temp = hv_store(href, "OFFSET", 6, newSViv(rr->number), 0);
-       if (rr->request_format_raw != 0) {
-           oid_dotted = oid2dotted(rr->request_format_raw);
+       if (rr->request_format != 0) {
+           oid_dotted = oid2dotted(rr->request_format);
        } else {
            /* Probably an SRU request: assume XML is required */
            oid_dotted = wrbuf_alloc();
@@ -832,13 +842,32 @@ int bend_fetch(void *handle, bend_fetch_rr *rr)
                                rr->errcode = 26;
                        }
                }
+               else if (composition->which == Z_RecordComp_complex)
+               {
+                       if (composition->u.complex->generic &&
+
+                                       composition->u.complex->generic &&
+                                       composition->u.complex->generic->elementSpec &&
+                                       composition->u.complex->generic->elementSpec->which ==
+                                       Z_ElementSpec_elementSetName)
+                       {
+                               complex = composition->u.complex;
+                               hv_store(href, "COMP", 4,
+                                       newSVpv(complex->generic->elementSpec->u.elementSetName, 0), 0);
+                       }
+                       else
+                       {
+#if 0  /* For now ignore this error, which is ubiquitous in SRU */
+                               fprintf(stderr, "complex is weird\n");
+                               rr->errcode = 26;
+                               return 0;
+#endif /*0*/
+                       }
+               }
                else
                {
-                       /* This is where we end up in the case of
-                        * SRU.  Since record composition ("element
-                        * sets") are meaningless in SRU anyway, we
-                        * just skip this.
-                        */
+                       rr->errcode = 26;
+                       return 0;
                }
        }
 
@@ -874,6 +903,16 @@ int bend_fetch(void *handle, bend_fetch_rr *rr)
        temp = hv_fetch(href, "REP_FORM", 8, 1);
        rep_form = newSVsv(*temp);
 
+       temp = hv_fetch(href, "SCHEMA", 6, 1);
+       if (temp != 0) {
+               schema = newSVsv(*temp);
+               ptr = SvPV(schema, length);
+               if (length > 0) {
+                       rr->schema = (char *)odr_malloc(rr->stream, length + 1);
+                       strcpy(rr->schema, ptr);
+               }
+       }
+
        temp = hv_fetch(href, "HANDLE", 6, 1);
        point = newSVsv(*temp);
 
@@ -886,16 +925,18 @@ int bend_fetch(void *handle, bend_fetch_rr *rr)
        rr->basename = ODR_basename;
 
        ptr = SvPV(rep_form, length);
-       ODR_oid_buf = (int *)odr_malloc(rr->stream, (MAX_OID + 1) * sizeof(int));
-       if (dotted2oid(ptr, ODR_oid_buf) == -1)         /* Maximum number of OID elements exceeded */
+
+       rr->output_format = yaz_string_to_oid_odr(yaz_oid_std(),
+                                       CLASS_RECSYN, ptr, rr->stream);
+       if (!rr->output_format)
        {
-               printf("Net::Z3950::SimpleServer: WARNING: OID structure too long, max length is %d\n", MAX_OID);
+               printf("Net::Z3950::SimpleServer: WARNING: Bad OID %s\n", ptr);
+               rr->output_format =
+                       odr_oiddup(rr->stream, yaz_oid_recsyn_sutrs);
        }
-       rr->output_format_raw = ODR_oid_buf;    
-       
        ptr = SvPV(record, length);
-       oid = oid_getentbyoid(ODR_oid_buf);
-       if (oid->value == VAL_GRS1)             /* Treat GRS-1 records separately */
+        /* Treat GRS-1 records separately */
+       if (!oid_oidcmp(rr->output_format, yaz_oid_recsyn_grs_1))
        {
                rr->record = (char *) read_grs1(ptr, rr->stream);
                rr->len = -1;
@@ -921,7 +962,7 @@ int bend_fetch(void *handle, bend_fetch_rr *rr)
        }
        rr->surrogate_flag = SvIV(sur_flag);
 
-       wrbuf_free(oid_dotted, 1);
+       wrbuf_destroy(oid_dotted);
        sv_free((SV*) href);
        sv_free(basename);
        sv_free(record);
@@ -931,6 +972,9 @@ int bend_fetch(void *handle, bend_fetch_rr *rr)
        sv_free(sur_flag);
        sv_free(rep_form);
 
+       if (schema)
+               sv_free(schema);
+
        PUTBACK;
        FREETMPS;
        LEAVE;
@@ -950,6 +994,7 @@ int bend_present(void *handle, bend_present_rr *rr)
        STRLEN len;
        Z_RecordComposition *composition;
        Z_ElementSetNames *simple;
+       Z_CompSpec *complex;
        char *ODR_errstr;
        char *ptr;
        Zfront_handle *zhandle = (Zfront_handle *)handle;
@@ -988,6 +1033,25 @@ int bend_present(void *handle, bend_present_rr *rr)
                                return 0;
                        }
                }
+               else if (composition->which == Z_RecordComp_complex)
+               {
+                       if (composition->u.complex->generic &&
+
+                                       composition->u.complex->generic &&
+                                       composition->u.complex->generic->elementSpec &&
+                                       composition->u.complex->generic->elementSpec->which ==
+                                       Z_ElementSpec_elementSetName)
+                       {
+                               complex = composition->u.complex;
+                               hv_store(href, "COMP", 4,
+                                       newSVpv(complex->generic->elementSpec->u.elementSetName, 0), 0);
+                       }
+                       else
+                       {
+                               rr->errcode = 26;
+                               return 0;
+                       }
+               }
                else
                {
                        rr->errcode = 26;
@@ -1090,7 +1154,7 @@ int bend_scan(void *handle, bend_scan_rr *rr)
        if (rr->term->term->which == Z_Term_general)
        {
                term_len = rr->term->term->u.general->len;
-               hv_store(href, "TERM", 4, newSVpv(rr->term->term->u.general->buf, term_len), 0);
+               hv_store(href, "TERM", 4, newSVpv((char*) rr->term->term->u.general->buf, term_len), 0);
        } else {
                rr->errcode = 229;      /* Unsupported term type */
                return 0;
@@ -1186,6 +1250,48 @@ int bend_scan(void *handle, bend_scan_rr *rr)
         return 0;
 }
 
+int bend_explain(void *handle, bend_explain_rr *q)
+{
+       HV *href;
+       CV *handler_cv = 0;
+       SV **temp;
+       char *explain;
+       SV *explainsv;
+       STRLEN len;
+       Zfront_handle *zhandle = (Zfront_handle *)handle;
+
+       dSP;
+       ENTER;
+       SAVETMPS;
+
+       href = newHV();
+       hv_store(href, "EXPLAIN", 7, newSVpv("", 0), 0);
+       hv_store(href, "DATABASE", 8, newSVpv(q->database, 0), 0);
+       hv_store(href, "HANDLE", 6, zhandle->handle, 0);
+
+       PUSHMARK(sp);
+       XPUSHs(sv_2mortal(newRV((SV*) href)));
+       PUTBACK;
+
+       handler_cv = simpleserver_sv2cv(explain_ref);
+       perl_call_sv((SV*) handler_cv, G_SCALAR | G_DISCARD);
+
+       SPAGAIN;
+
+       temp = hv_fetch(href, "EXPLAIN", 7, 1);
+       explainsv = newSVsv(*temp);
+
+       PUTBACK;
+       FREETMPS;
+       LEAVE;
+
+       explain = SvPV(explainsv, len);
+       q->explain_buf = (char*) odr_malloc(q->stream, len + 1);
+       strcpy(q->explain_buf, explain);
+
+        return 0;
+}
+
 bend_initresult *bend_init(bend_initrequest *q)
 {
        int dummy = simpleserver_clone();
@@ -1207,7 +1313,11 @@ bend_initresult *bend_init(bend_initrequest *q)
 
        zhandle->nmem = nmem;
        zhandle->stop_flag = 0;
-       /*q->bend_sort = bend_sort;*/
+
+        if (sort_ref)
+        {
+            q->bend_sort = bend_sort;
+        }
        if (search_ref)
        {
                q->bend_search = bend_search;
@@ -1226,6 +1336,10 @@ bend_initresult *bend_init(bend_initrequest *q)
        {
                q->bend_scan = bend_scan;
        }
+       if (explain_ref)
+       {
+               q->bend_explain = bend_explain;
+       }
 
                href = newHV(); 
        hv_store(href, "IMP_ID", 6, newSVpv("", 0), 0);
@@ -1418,6 +1532,11 @@ set_scan_handler(arg)
        CODE:
                scan_ref = newSVsv(arg);
 
+void
+set_explain_handler(arg)
+               SV *arg
+       CODE:
+               explain_ref = newSVsv(arg);
 
 int
 start_server(...)
@@ -1438,7 +1557,7 @@ start_server(...)
                }
                *argv_buf = NULL;
                root_perl_context = PERL_GET_CONTEXT;
-               nmem_mutex_create(&simpleserver_mutex);
+               yaz_mutex_create(&simpleserver_mutex);
 #if 0
                /* only for debugging perl_clone .. */
                tst_clones();